1. Field of the Invention
The invention relates broadly to devices known as jet pumps. This invention relates particularly to an improved jet pump for intimately mixing a primary fluid with a secondary fluid.
2. Description of the Prior Art
There are a multitude of requirements in an industrial setting for the mixing of a first fluid with a second fluid within an environment. Applications include, for example, mixing of liquids within a tank, combustion processes, chemical reactions, heat transfer processes, environmental control systems, and sprayers. In various applications, including waste treatment, it is desirable additional or independently, to entrain gases, including air, within a liquid.
Jet pumps or eductors are currently used to mix a first liquid with a second liquid by introducing the first liquid into the second mixture at a relatively high pressure through a restrictive flow orifice. Both jet pumps and eductors are based on the Venturi principle and the Bernoulli effect relating to the phenomenon of internal pressure reduction with increased stream velocity in a fluid.
Various commercially available eductors are described in product brochures, including DEX (TM) Tank Mixing Eductors. GEA Wiegand GmbH discloses liquid jet mixers. Fox Venturi eductors are commercially available to mix particulate solids with air and to Convey the air/solid mixture through a discharge outlet. Penberthy discloses jet pumps for pumping gases and circulating tank eductors to mix liquids in open or enclosed tanks.
Von Ohain, et al., U.S. Pat. No. 3,525,474 discloses an eductor having a convergent inlet section, a mixing section, and a divergent diffuser section with nozzles injecting high velocity primary jet fluids into the inlet section and by aspirator action inducing a secondary flow into the inlet.
Chambers U.S. Pat. No. 3,371,618 discloses a jet pump including a mixing chamber having a substantially constant static pressure throughout the mixing chamber wherein the induced flow of secondary fluid into the chamber is in a direction generally parallel to that of the primary fluid with the angle of divergence of the mixing chamber being approximately equal to the angle of expansion of the primary fluid in the mixing chamber, thereby minimizing energy losses.
Svantesson U.S. Pat. No. 3,799,511 discloses a method of forming a solution of gas and liquid and introducing such solution into a body of liquid comprising mixing a gas and liquid at sufficient pressure and for a sufficient period of time and then introducing the mixture, free of turbulence, into the body of liquid below the liquid surface level.
Alperin U.S. Pat. No. 4,332,529 discloses a jet diffuser ejector constructed for maximum thrust augmentation with minimal length comprising multiple primary injection nozzles arranged in spaced relationship at pre-selected angles.
Ho, et al., U.S. Pat. No. 4,519,423 discloses an apparatus for mixing fluids having at least one non-circular orifice, the orifice having unequal major and minor axis dimensions, and the mixing region extending downstream a distance at least equal to the minor axis dimension.
Straub, et al., U.S. Pat. No. 4,792,284 discloses a device for creating a pressure difference in the flow of a fluid comprising a double cone, the double cone consisting of two co-axial hollow cones linked at their smallest faces. A lateral connection is provided at the narrowest point of the double cone linking the faces. A negative pressure at the narrowest point produces a sucking effect at the lateral connection.
Schreiber, et al, U. S. Pat. No. 4,818,446 discloses an apparatus for introducing a gas into a fluid in which a diffuser pipe or a perforated distributor hose is mounted on a gas supply pipe.
Tharp, U.S. Pat. No. 4,960,546, discloses an improved mounting bracket for mounting diffusers on submerged lateral air supply pipes in a wastewater treatment system.
Ealba, et al, U.S. Pat. No. 4,971,678 discloses a diffuser with a thin convoluted wall member disposed upstream of the inlet which generates vortices having axes in the downstream direction. The vortices enhance mixing within the diffuser. Tharp, U.S. Pat. No. 5,013,493, discloses a staggered diffuser arrangement for wastewater treatment systems in which tubular diffusers are arranged with short and long diffuser assemblies
Emmett, Jr., et al, U.S. Pat. No. 5,057,284, discloses a reactor vessel for use of treating slurries which contains a mixer arrangement and an air supply arrangement.
Tharp, U.S. Pat. No. 5,059,358 discloses a tubular diffuser for a wastewater aeration system comprising a pipe having spaced-apart outlet ports and a porous membrane sleeved around the pipe for discharging air and bubbles and an adjustable plug which can be located at various locations within the pipe to provide buoyant and non-buoyant use of the diffuser.
It is an object of the present invention to provide an improved jet pump for intimately mixing a primary fluid with a secondary fluid.
It is another object of the present invention to provide an improved jet pump for intimately mixing a primary fluid with a secondary fluid within a relatively confined area.
It is another object of the present invention to provide an improved jet pump for mixing a primary fluid with a secondary fluid, the jet pump being disposed in an environment comprising the secondary fluid.